Nortec ME Control - Manual (Page 56)

56 Maintenance
6.7 Routine water sampling and testing
Hygiene
Your attention is drawn to local regulations and bylaws regarding the control of Legionellosis in water
systems. If inadequately maintained, water systems, of which any humidifier is a part, can support the
growth of micro-organisms, including the bacterium that causes Legionnaires’ disease. Nortec Humid-
ity Ltd. has considered all aspects of this equipment to reduce as far as possible the risk of Legionnaires’
disease and other similar conditions, but it is important that users are aware of their responsibilities under
local regulations in reducing the risk of Legionellosis.
To prevent the growth of Legionella, users are required to:
1. Carry out a risk assessment of the water system using a competent person, and implement an ap-
propriate monitoring and control regime.
2. Avoid water temperatures which favour the growth of Legionella.
3. Avoid water stagnation.
4. Clean and disinfect the system in accordance with local regulations and bylaws, and the instructions
in this manual.
5. The Nortec ME Control system must be connected to a clean, wholesome mains water sup-
ply and it is recommended that the supply water is chlorinated. It is the responsibility of the user to
ensure that the water system complies with local regulations and bylaws, particularly those for the
control of Legionella microbes. The use of mains water fed tanks and reservoirs is only permitted
as part of a managed water treatment system.
On commissioning and at regular intervals thereafter, test for possible water contamination using dipslides.
Take samples from the water supply, the ev aporative cassettes a nd from the tank. Check for biofilm.
The dipslides should be incubated for 2 days at 30°C (86°F).
1. If the microbial count from the tank exceeds 10
3 cfu/ml, the system should be turned off, any biofilm
scrubbed clean and then disinfected using a 50 ppm chlorine solution for one hour before being put
back into use.
2. If the microbial count in the water supply to the evaporative module exceeds 10 3 cfu/ml, this sug-
gests contamination of the water system within the building. The system should be turned off and
you should seek specialist advice on cleaning your water supply.
3. If the water temperature anywhere in the system regularly exceeds 20°C, (68°F) increase the fre-
quency of water sampling. The frequency may be reduced if successive tests show a consistent
level below 10 3 cfu/ml.